LiteLLM
The default answer in this category, and it earns that. Widest provider coverage anywhere, a Rust core with a Python SDK, and commits landing daily.
Open-source AI infrastructure
Best Open-Source AI Gateways in 2026
Seven open-source AI gateways compared on the fact that decides most adoptions: which capabilities stop working when you self-host without paying. Licences, tier bo…
Bifrost
Maxim AI's gateway, and a genuinely well-engineered one. A Go binary built for low overhead, claiming under 100 microseconds at 5,000 requests per second and 50x faster than LiteLLM. Those are their numbers and we have not benchmarked them, but the engineering focus is real and the deployment story is simple: Docker, Kubernetes, or a single binary.
Kong AI Gateway
Kong Gateway itself is properly Apache-2.0 and has years of production hardening behind it. If you already run Kong for your APIs, adding AI traffic to a gateway your team already operates is a strong argument that beats most feature comparisons.
Helicone
Stars: 6,116. Licence: Apache-2.0, no enterprise directory. In maintenance mode since March 2026.
OpenRouter
It belongs on this list because it comes up in every one of these searches, and because it is genuinely excellent at its actual job, which is not the one this post is about.
Cloudflare AI Gateway
Same caveat, same reason for inclusion. It is a Cloudflare platform service: analytics and logging, caching served from Cloudflare's edge instead of the model provider, rate limiting, and retry with model fallback.